[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 17.143735] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 18.454007] random: sshd: uninitialized urandom read (32 bytes read) [ 18.753483] random: sshd: uninitialized urandom read (32 bytes read) [ 19.498448] random: sshd: uninitialized urandom read (32 bytes read) [ 24.759622] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.10.49' (ECDSA) to the list of known hosts. [ 30.209604] random: sshd: uninitialized urandom read (32 bytes read) executing program [ 30.297756] ================================================================== [ 30.305290] BUG: KASAN: slab-out-of-bounds in pdu_read+0x90/0xd0 [ 30.311459] Read of size 48318 at addr ffff8801ba1b842d by task syz-executor306/4484 [ 30.319329] [ 30.320955] CPU: 0 PID: 4484 Comm: syz-executor306 Not tainted 4.18.0-rc3-next-20180709+ #2 [ 30.329424] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 30.338846] Call Trace: [ 30.341438] dump_stack+0x1c9/0x2b4 [ 30.345067] ? dump_stack_print_info.cold.2+0x52/0x52 [ 30.350249] ? printk+0xa7/0xcf [ 30.353514] ? kmsg_dump_rewind_nolock+0xe4/0xe4 [ 30.358254] ? pdu_read+0x90/0xd0 [ 30.361691] print_address_description+0x6c/0x20b [ 30.366524] ? pdu_read+0x90/0xd0 [ 30.369965] kasan_report.cold.7+0x242/0x30d [ 30.374358] check_memory_region+0x13e/0x1b0 [ 30.378803] memcpy+0x23/0x50 [ 30.381894] pdu_read+0x90/0xd0 [ 30.385156] p9pdu_readf+0x579/0x2170 [ 30.388947] ? p9pdu_writef+0xe0/0xe0 [ 30.392759] ? ksys_dup3+0x690/0x690 [ 30.396473] ? check_same_owner+0x340/0x340 [ 30.400790] ? p9_fd_poll+0x2b0/0x2b0 [ 30.404587] ? kasan_kmalloc+0xc4/0xe0 [ 30.408464] ? kasan_unpoison_shadow+0x35/0x50 [ 30.413040] ? p9_fd_show_options+0x1c0/0x1c0 [ 30.417536] ? __raw_spin_lock_init+0x2d/0x100 [ 30.422112] p9_client_create+0xde0/0x16c9 [ 30.426332] ? p9_client_read+0xc60/0xc60 [ 30.430579] ? lock_acquire+0x1e4/0x540 [ 30.434555] ? lock_acquire+0x1e4/0x540 [ 30.438518] ? fs_reclaim_acquire+0x20/0x20 [ 30.442824] ? lock_release+0xa30/0xa30 [ 30.446872] ? __lockdep_init_map+0x105/0x590 [ 30.451367] ? kasan_check_write+0x14/0x20 [ 30.455603] ? __init_rwsem+0x1cc/0x2a0 [ 30.459575] ? do_raw_write_unlock.cold.8+0x49/0x49 [ 30.464590] ? __kmalloc_track_caller+0x311/0x760 [ 30.469422] ? save_stack+0xa9/0xd0 [ 30.473044] ? save_stack+0x43/0xd0 [ 30.476753] ? kasan_kmalloc+0xc4/0xe0 [ 30.480640] ? kmem_cache_alloc_trace+0x152/0x780 [ 30.485475] ? memcpy+0x45/0x50 [ 30.488761] v9fs_session_init+0x21a/0x1a80 [ 30.493075] ? rcu_note_context_switch+0x730/0x730 [ 30.497993] ? do_mount+0x69e/0x1fb0 [ 30.501697] ? lock_acquire+0x1e4/0x540 [ 30.505678] ? v9fs_show_options+0x7e0/0x7e0 [ 30.510073] ? lock_release+0xa30/0xa30 [ 30.514127] ? check_same_owner+0x340/0x340 [ 30.518443] ? lock_downgrade+0x8f0/0x8f0 [ 30.522577] ? kasan_unpoison_shadow+0x35/0x50 [ 30.527143] ? kasan_kmalloc+0xc4/0xe0 [ 30.531019] ? kmem_cache_alloc_trace+0x318/0x780 [ 30.535847] ? kasan_unpoison_shadow+0x35/0x50 [ 30.540411] ? kasan_kmalloc+0xc4/0xe0 [ 30.544289] v9fs_mount+0x7c/0x900 [ 30.547812] ? v9fs_drop_inode+0x150/0x150 [ 30.552038] legacy_get_tree+0x118/0x440 [ 30.556092] vfs_get_tree+0x1cb/0x5c0 [ 30.559876] do_mount+0x6c1/0x1fb0 [ 30.563402] ? check_same_owner+0x340/0x340 [ 30.567715] ? lock_release+0xa30/0xa30 [ 30.571690] ? copy_mount_string+0x40/0x40 [ 30.575920] ? kasan_kmalloc+0xc4/0xe0 [ 30.579801] ? kmem_cache_alloc_trace+0x318/0x780 [ 30.584638] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 30.590169] ? _copy_from_user+0xdf/0x150 [ 30.594318] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 30.599844] ? copy_mount_options+0x285/0x380 [ 30.604410] ksys_mount+0x12d/0x140 [ 30.608026] __x64_sys_mount+0xbe/0x150 [ 30.612003] do_syscall_64+0x1b9/0x820 [ 30.615885] ? syscall_return_slowpath+0x5e0/0x5e0 [ 30.620809] ? syscall_return_slowpath+0x31d/0x5e0 [ 30.625734] ? prepare_exit_to_usermode+0x3b0/0x3b0 [ 30.630739] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 30.636261] ? prepare_exit_to_usermode+0x291/0x3b0 [ 30.641262] ? perf_trace_sys_enter+0xb10/0xb10 [ 30.645925] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 30.650755] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 30.655925] RIP: 0033:0x440239 [ 30.659108] Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 fb 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00 [ 30.678235] RSP: 002b:00007ffc7c5cb3f8 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5 [ 30.685929] RAX: ffffffffffffffda RBX: ffffffffffffffff RCX: 0000000000440239 [ 30.693179] RDX: 00000000200000c0 RSI: 0000000020000080 RDI: 0000000000000000 [ 30.700437] RBP: 0030656c69662f2e R08: 0000000020000380 R09: 00000000004002c8 [ 30.707687] R10: 0000000000000000 R11: 0000000000000202 R12: 64663d736e617274 [ 30.714954] R13: 0000000000401b50 R14: 0000000000000000 R15: 0000000000000000 [ 30.722209] [ 30.723826] Allocated by task 4484: [ 30.727463] save_stack+0x43/0xd0 [ 30.730904] kasan_kmalloc+0xc4/0xe0 [ 30.734605] __kmalloc+0x14e/0x760 [ 30.738136] p9_fcall_alloc+0x1e/0x90 [ 30.741920] p9_client_prepare_req.part.9+0x754/0xcd0 [ 30.747092] p9_client_rpc+0x1bd/0x1400 [ 30.751076] p9_client_create+0xd09/0x16c9 [ 30.755298] v9fs_session_init+0x21a/0x1a80 [ 30.759613] v9fs_mount+0x7c/0x900 [ 30.763138] legacy_get_tree+0x118/0x440 [ 30.767192] vfs_get_tree+0x1cb/0x5c0 [ 30.770972] do_mount+0x6c1/0x1fb0 [ 30.774490] ksys_mount+0x12d/0x140 [ 30.778098] __x64_sys_mount+0xbe/0x150 [ 30.782052] do_syscall_64+0x1b9/0x820 [ 30.785928] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 30.791090] [ 30.792874] Freed by task 0: [ 30.795891] (stack is not available) [ 30.799604] [ 30.801223] The buggy address belongs to the object at ffff8801ba1b8400 [ 30.801223] which belongs to the cache kmalloc-16384 of size 16384 [ 30.814223] The buggy address is located 45 bytes inside of [ 30.814223] 16384-byte region [ffff8801ba1b8400, ffff8801ba1bc400) [ 30.826169] The buggy address belongs to the page: [ 30.831085] page:ffffea0006e86e00 count:1 mapcount:0 mapping:ffff8801da802200 index:0x0 compound_mapcount: 0 [ 30.841037] flags: 0x2fffc0000008100(slab|head) [ 30.845721] raw: 02fffc0000008100 ffffea0006ce7a08 ffff8801da801c48 ffff8801da802200 [ 30.853586] raw: 0000000000000000 ffff8801ba1b8400 0000000100000001 0000000000000000 [ 30.861444] page dumped because: kasan: bad access detected [ 30.867135] [ 30.868740] Memory state around the buggy address: [ 30.873650] ffff8801ba1ba300: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 30.880989] ffff8801ba1ba380: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 30.888349] >ffff8801ba1ba400: 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc [ 30.895705] ^ [ 30.900102] ffff8801ba1ba480: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 30.908685] ffff8801ba1ba500: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 30.916039] ================================================================== [ 30.923586] Kernel panic - not syncing: panic_on_warn set ... [ 30.923586] [ 30.931013] CPU: 0 PID: 4484 Comm: syz-executor306 Tainted: G B 4.18.0-rc3-next-20180709+ #2 [ 30.940884] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 30.950224] Call Trace: [ 30.952803] dump_stack+0x1c9/0x2b4 [ 30.956419] ? dump_stack_print_info.cold.2+0x52/0x52 [ 30.961595] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 30.966344] panic+0x238/0x4e7 [ 30.969537] ? add_taint.cold.5+0x16/0x16 [ 30.973671] ? do_raw_spin_unlock+0xa7/0x2f0 [ 30.978071] ? pdu_read+0x90/0xd0 [ 30.981704] kasan_end_report+0x47/0x4f [ 30.985656] kasan_report.cold.7+0x76/0x30d [ 30.989960] check_memory_region+0x13e/0x1b0 [ 30.994353] memcpy+0x23/0x50 [ 30.997469] pdu_read+0x90/0xd0 [ 31.000754] p9pdu_readf+0x579/0x2170 [ 31.004537] ? p9pdu_writef+0xe0/0xe0 [ 31.008322] ? ksys_dup3+0x690/0x690 [ 31.012204] ? check_same_owner+0x340/0x340 [ 31.016506] ? p9_fd_poll+0x2b0/0x2b0 [ 31.027413] ? kasan_kmalloc+0xc4/0xe0 [ 31.031286] ? kasan_unpoison_shadow+0x35/0x50 [ 31.035861] ? p9_fd_show_options+0x1c0/0x1c0 [ 31.040345] ? __raw_spin_lock_init+0x2d/0x100 [ 31.044932] p9_client_create+0xde0/0x16c9 [ 31.049168] ? p9_client_read+0xc60/0xc60 [ 31.053321] ? lock_acquire+0x1e4/0x540 [ 31.057278] ? lock_acquire+0x1e4/0x540 [ 31.061243] ? fs_reclaim_acquire+0x20/0x20 [ 31.065547] ? lock_release+0xa30/0xa30 [ 31.069504] ? __lockdep_init_map+0x105/0x590 [ 31.073983] ? kasan_check_write+0x14/0x20 [ 31.078209] ? __init_rwsem+0x1cc/0x2a0 [ 31.082163] ? do_raw_write_unlock.cold.8+0x49/0x49 [ 31.087172] ? __kmalloc_track_caller+0x311/0x760 [ 31.092151] ? save_stack+0xa9/0xd0 [ 31.095763] ? save_stack+0x43/0xd0 [ 31.099564] ? kasan_kmalloc+0xc4/0xe0 [ 31.103540] ? kmem_cache_alloc_trace+0x152/0x780 [ 31.108365] ? memcpy+0x45/0x50 [ 31.111631] v9fs_session_init+0x21a/0x1a80 [ 31.115941] ? rcu_note_context_switch+0x730/0x730 [ 31.120855] ? do_mount+0x69e/0x1fb0 [ 31.124674] ? lock_acquire+0x1e4/0x540 [ 31.128643] ? v9fs_show_options+0x7e0/0x7e0 [ 31.133032] ? lock_release+0xa30/0xa30 [ 31.136996] ? check_same_owner+0x340/0x340 [ 31.141668] ? lock_downgrade+0x8f0/0x8f0 [ 31.146077] ? kasan_unpoison_shadow+0x35/0x50 [ 31.150643] ? kasan_kmalloc+0xc4/0xe0 [ 31.154716] ? kmem_cache_alloc_trace+0x318/0x780 [ 31.159542] ? kasan_unpoison_shadow+0x35/0x50 [ 31.164160] ? kasan_kmalloc+0xc4/0xe0 [ 31.168036] v9fs_mount+0x7c/0x900 [ 31.171576] ? v9fs_drop_inode+0x150/0x150 [ 31.175881] legacy_get_tree+0x118/0x440 [ 31.180066] vfs_get_tree+0x1cb/0x5c0 [ 31.183852] do_mount+0x6c1/0x1fb0 [ 31.187400] ? check_same_owner+0x340/0x340 [ 31.191818] ? lock_release+0xa30/0xa30 [ 31.195873] ? copy_mount_string+0x40/0x40 [ 31.200204] ? kasan_kmalloc+0xc4/0xe0 [ 31.204167] ? kmem_cache_alloc_trace+0x318/0x780 [ 31.209079] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 31.214864] ? _copy_from_user+0xdf/0x150 [ 31.218994] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 31.224604] ? copy_mount_options+0x285/0x380 [ 31.229193] ksys_mount+0x12d/0x140 [ 31.232798] __x64_sys_mount+0xbe/0x150 [ 31.236757] do_syscall_64+0x1b9/0x820 [ 31.240633] ? syscall_return_slowpath+0x5e0/0x5e0 [ 31.246499] ? syscall_return_slowpath+0x31d/0x5e0 [ 31.251420] ? prepare_exit_to_usermode+0x3b0/0x3b0 [ 31.256421] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 31.261938] ? prepare_exit_to_usermode+0x291/0x3b0 [ 31.266936] ? perf_trace_sys_enter+0xb10/0xb10 [ 31.271591] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 31.276507] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 31.281852] RIP: 0033:0x440239 [ 31.285018] Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 fb 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00 [ 31.305977] RSP: 002b:00007ffc7c5cb3f8 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5 [ 31.313667] RAX: ffffffffffffffda RBX: ffffffffffffffff RCX: 0000000000440239 [ 31.320923] RDX: 00000000200000c0 RSI: 0000000020000080 RDI: 0000000000000000 [ 31.328182] RBP: 0030656c69662f2e R08: 0000000020000380 R09: 00000000004002c8 [ 31.335702] R10: 0000000000000000 R11: 0000000000000202 R12: 64663d736e617274 [ 31.343038] R13: 0000000000401b50 R14: 0000000000000000 R15: 0000000000000000 [ 31.351056] Dumping ftrace buffer: [ 31.354596] (ftrace buffer empty) [ 31.358286] Kernel Offset: disabled [ 31.362253] Rebooting in 86400 seconds..